Trump, who is spending the holidays at his Florida resort, Mar-a-Lago, also sent Christmas greetings to deployed military personnel, praising them for success in the fight against terrorism.
The early-morning swipe at McCabe followed a flurry of tweets attacking the deputy FBI chief on Saturday. McCabe, who has been a lightning rod for Republican attacks on the FBI, is expected to retire early in the new year.
Critics say the president and his allies are in the midst of a systematic campaign to denigrate the FBI and special counsel Robert S. Mueller III, who is looking into potential collusion by the Trump campaign in Russia's attempts to sway the 2016 presidential election.
In a pair of statements on Twitter, Trump again expressed scorn regarding news coverage of his administration. For months, the president has been particularly critical of reports regarding the Russia investigation and more recently has repeatedly complained he does not receive enough credit for a booming stock market.
In his video conference message to troops overseas, the president made apparent reference to the fight against the militants of Islamic State, who over the last year have lost most of the territory they previously controlled in Iraq and Syria, including former strongholds in Mosul and Raqqa.
"We're winning," Trump told military personnel deployed in Qatar, Kuwait, Guantanamo Bay and aboard the guided missile destroyer Sampson.
Reporters traveling with the president heard his address, but were ushered from the room before he took questions from the troops. The president often breaks with longtime custom and makes politically charged statements at events in which he addresses military personnel.
